It is well known in the engine valve train art to provide a valve actuator with a domed pivot socket such as a pivot recess of a finger follower or a push rod socket of a rocker arm. The pivot socket may communicate with a source of lubricating oil and include an opening for spraying oil from the socket through its dome for lubricating associated components of the valve mechanism. In a finger follower, for example, a hydraulic lash adjuster may act as a pivot about which the follower is actuated by a cam of a camshaft to open and close an associated valve of an engine. Lubrication of the cam and cam follower may be provided by spraying oil from the lash adjuster through an opening in a pivot socket of the finger follower into the camshaft compartment where it lubricates the cam, the follower, and the valve actuating pad or pallet of the finger follower.
With the currently common use of roller cam followers, it is possible to reduce the amount of lubricant supplied to the cam followers, and therefore reduce the amount of energy required by the oil pump for pumping lubricant in the engine. To accomplish this, in the most efficient manner, requires a lubricant passage designed for ease and accuracy of manufacture and arranged to aim lubricant directly at the surface of the roller follower, preferably near its line of contact with the associated cam.